This invention relates generally to the master cylinder of an offset or the like printing press and more particularly to such a master cylinder which includes means for changing the length of the surface thereof provided for receiving master sheets thereby to accommodate sheets of different lengths.
Conventionally, master cylinders used in offset and the like printing presses are provided with a master receiving surface of a predetermined length. At each end of the surface of the cylinder there is provided a clamping member for holding the lead and trailing ends, respectively, of the sheet. The cylinder is not constructed to receive a master sheet of a length different than that for which it was designed. Thus, persons using an offset and the like press of the type described are restricted for the most part to using master sheets of a length which corresponds to the particular master cylinder included in the press.
The prior art reveals various schemes for accommodating different size master sheets on a single master cylinder. One such scheme employs an arcuate cylinder section which is removably attached to a master cylinder to accommodate a longer than "standard" master sheet. While this scheme provides high quality printing, the attachment and removal of the section including the trailing end clamp normally coupled to the stationary master receiving surface of the cylinder, is time-consuming and the section can be easily damaged in the process. Futhermore, once the section is removed from the cylinder, there is the problem of storage thereof in a safe place.